The goal of saving entropy in Fortuna is two-fold: (1) to provide early
availability of the random device (unblocking) on next boot; and (2), to
have known, high-quality entropy available for that initial seed. We know
it is high quality because it's output taken from Fortuna.
The FS&K paper makes it clear that Fortuna unblocks when enough bits have
been input that the output //may// be safely seeded. But they emphasize
that the quality of various entropy sources is unknown, and a saved entropy
file is essential for both availability and ensuring initial
unpredictability.
In FreeBSD we persist entropy using two mechanisms:
1. The /etc/rc.d/random shutdown() function, which is used for ordinary
shutdowns and reboots; and,
2. A cron job that runs every dozen minutes or so to persist new entropy, in
case the system suffers from power loss or a crash (bypassing the
ordinary shutdown path).
Filesystems are free to cache dirty data indefinitely, with arbitrary flush
policy. Fsync must be used to ensure the data is persisted, especially for
the cron job save-entropy, whose entire goal is power loss and crash safe
entropy persistence.
Ordinary shutdown may not need the fsync because unmount should flush out
the dirty entropy file shortly afterwards. But it is always possible power
loss or crash occurs during the short window after rc.d/random shutdown runs
and before the filesystem is unmounted, so the additional fsync there seems
harmless.
PR: 230876
Reviewed by: delphij, markj, markm
Approved by: secteam (delphij)
Differential Revision: https://reviews.freebsd.org/D19742
Each control message region must be aligned on a 4-byte boundary on 32-bit
architectures. The 32-bit compat shim for recvmsg() gets the actual layout
right, but doesn't pad the payload length when computing msg_controllen for
the output message header. If a control message contains an unaligned
payload, such as the 1-byte TTL field in the example attached to PR 236737,
this can produce control message payload boundaries that extend beyond
the boundary reported by msg_controllen.
PR: 236737
Reported by: Yuval Pavel Zholkover <paulzhol@gmail.com>
Reviewed by: markj
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D19768
stf(4) interfaces are not multicast-capable so they can't perform DAD.
They also did not set IFF_DRV_RUNNING when an address was assigned, so
the logic in nd6_timer() would periodically flag such an address as
tentative, resulting in interface flapping.
Fix the problem by setting IFF_DRV_RUNNING when an address is assigned,
and do some related cleanup:
- In in6if_do_dad(), remove a redundant check for !UP || !RUNNING.
There is only one caller in the tree, and it only looks at whether
the return value is non-zero.
- Have in6if_do_dad() return false if the interface is not
multicast-capable.
- Set ND6_IFF_NO_DAD when an address is assigned to an stf(4) interface
and the interface goes UP as a result. Note that this is not
sufficient to fix the problem because the new address is marked as
tentative and DAD is started before in6_ifattach() is called.
However, setting no_dad is formally correct.
- Change nd6_timer() to not flag addresses as tentative if no_dad is
set.
This is based on a patch from Viktor Dukhovni.
Reported by: Viktor Dukhovni <ietf-dane@dukhovni.org>
Reviewed by: ae
MFC after: 3 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D19751
This is particularly useful when installing programs for tests that need to be
linked statically, e.g., mini-me from capsicum-test, which is linked statically
to avoid the dynamic library lookup in the upstream project.
Reviewed by: emaste
Approved by: emaste (mentor)
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D19756
In particular, elf32 FreeBSD binaries were not executed on LP64 hosts.
The interp_name_len value should account for the nul terminator. This
is needed for strncmp()s in brand checking code to work.
Reported by: andreast
Sponsored by: The FreeBSD Foundation
MFC after: 12 days (together with r345661)
providers mediasize changes.
While here, use GEOM nomenclature to describe providers instead of calling
them device nodes.
Obtained from: Fudo Security
Tested in: AWS
The behavior prior to this change would not override default values if set in
`bsd.own.mk`, or (in the more general case) globally before `bsd.progs.mk` was
included. This affected `bsd.test.mk` as well, since it consumes
`bsd.progs.mk`.
Some examples of this failing behavior are as follows:
* `BINMODE` defaults to 0555 per `bsd.own.mk`. If someone wanted to set the
`BINMODE` to `NOBINMODE` (0444) for `prog`, for example, like
`BINMODE.prog= ${NOBINMODE}`, `bsd.progs.mk` would not honor the per-PROG
setting.
* An application, `prog`, does not build at `WARNS?= 6`. Before this change,
setting to a lower `WARNS` value, e.g., `WARNS.prog= 3`, would have been
impossible, requiring that `prog` be built from another directory,
the global `WARNS` be lowered, or a per-PROG value needing to be set
across the board. None of the above workarounds is desirable.
This change unbreaks variables defined in `PROG_OVERRIDE_VARS` which have
defaults set before `bsd.progs.mk` is included, by setting them to their
defined values if set on a per-PROG basis.
Reviewed by: asomers
Approved by: emaste (mentor)
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D19755
When comparing best frequencies use the absolute value.
If we do not do that we end up choosing an always lower value than
the best one if the exact freq cannot be met.
MFC after: 2 weeks
The current logic for CSTD/CXXSTD requires homogenity as far as the
supported C/C++ standards, which is a sensible default. However, when
dealing with differing versions of C++, some code may compile with C++11, but
not C++17 (for instance). So in order to avoid having people convert over their
code to the new standard, give the users the ability to specify the standard on
a per-program basis.
This will allow a user to override the supporting standard for a set of
programs, mixing C++11 with C++14 (for instance).
Reviewed by: asomers
Apprved by: emaste (mentor)
MFC after: 1 month
MFC with: r345708
Differential Revision: https://reviews.freebsd.org/D19738
CXXSTD was added as the C++ analogue to CSTD.
CXXSTD defaults to `-std=c++11` with supporting compilers; `-std=gnu++98`,
otherwise for older versions of g++.
This change standardizes the CXXSTD variable, originally added to
googletest.test.inc.mk as part of r345203.
As part of this effort, convert all `CXXFLAGS+= -std=*` calls to use `CXXSTD`.
Notes:
This value is not sanity checked in bsd.sys.mk, however, given the two
most used C++ compilers on FreeBSD (clang++ and g++) support both modes, it is
likely to work with both toolchains. This method will be refined in the future
to support more variants of C++, as not all versions of clang++ and g++ (for
instance) support C++14, C++17, etc.
Any manual appending of `-std=*` to `CXXFLAGS` should be replaced with CXXSTD.
Example:
Before this commit:
```
CXXFLAGS+= -std=c++14
```
After this commit:
```
CXXSTD= c++14
```
Reviewed by: asomers
Approved by: emaste (mentor)
MFC after: 1 month
MFC with: r345203, r345704, r345705
Relnotes: yes
Tested with: make tinderbox
Differential Revision: https://reviews.freebsd.org/D19732
When a review is closed via Phabricator it updates the patch attached to the
review. I downloaded the raw patch from Phabricator, applied it, and repeated
my mistake from r345704 by accident mixing content from D19732 and D19738.
For my own personal sanity, I will try not to mix reviews like this in the
future.
MFC after: 1 month
MFC with: r345706
Approved by: emaste (mentor, implicit)
CXXSTD was added as the C++ analogue to CSTD.
CXXSTD defaults to `-std=c++11` with supporting compilers; `-std=gnu++98`,
otherwise for older versions of g++.
This change standardizes the CXXSTD variable, originally added to
googletest.test.inc.mk as part of r345203.
As part of this effort, convert all `CXXFLAGS+= -std=*` calls to use `CXXSTD`.
Notes:
This value is not sanity checked in bsd.sys.mk, however, given the two
most used C++ compilers on FreeBSD (clang++ and g++) support both modes, it is
likely to work with both toolchains. This method will be refined in the future
to support more variants of C++, as not all versions of clang++ and g++ (for
instance) support C++14, C++17, etc.
Any manual appending of `-std=*` to `CXXFLAGS` should be replaced with CXXSTD.
Example:
Before this commit:
```
CXXFLAGS+= -std=c++14
```
After this commit:
```
CXXSTD= c++14
```
Reviewed by: asomers
Approved by: emaste (mentor)
MFC after: 1 month
MFC with: r345203, r345704, r345705
Relnotes: yes
Tested with: make tinderbox
Differential Revision: https://reviews.freebsd.org/D19732
I accidentally committed code from two reviews. I will reintroduce the code to
bsd.progs.mk as part of a separate commit from r345704.
Approved by: emaste (mentor, implicit)
MFC after: 2 months
MFC with: r345704
CXXSTD defaults to `-std=c++11` with supporting compilers; `-std=gnu++98`,
otherwise for older versions of g++.
This change standardizes the CXXSTD variable, originally added to
googletest.test.inc.mk as part of r345203.
As part of this effort, convert all `CXXFLAGS+= -std=*` calls to use `CXXSTD`.
Notes:
This value is not sanity checked in bsd.sys.mk, however, given the two
most used C++ compilers on FreeBSD (clang++ and g++) support both modes, it is
likely to work with both toolchains. This method will be refined in the future
to support more variants of C++, as not all versions of clang++ and g++ (for
instance) support C++14, C++17, etc.
Any manual appending of `-std=*` to `CXXFLAGS` should be replaced with CXXSTD.
Example:
Before this commit:
```
CXXFLAGS+= -std=c++14
```
After this commit:
```
CXXSTD= c++14
```
Reviewed by: asomers
Approved by: emaste (mentor)
MFC after: 1 month
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D19732
If dso uses initial exec TLS mode, rtld tries to allocate TLS in
static space. If there is no space left, the dlopen(3) fails. If space
if allocated, initial content from PT_TLS segment is distributed to
all threads' pcbs, which was missed and caused un-initialized TLS
segment for such dso after dlopen(3).
The mode is auto-detected either due to the relocation used, or if the
DF_STATIC_TLS dynamic flag is set. In the later case, the TLS segment
is tried to allocate earlier, which increases chance of the dlopen(3)
to succeed. LLD was recently fixed to properly emit the flag, ld.bdf
did it always.
Initial test by: dumbbell
Tested by: emaste (amd64), ian (arm)
Tested by: Gerald Aryeetey <aryeeteygerald_rogers.com> (arm64)
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D19072
Drop the adj_free field from vm_map_entry_t. Refine the max_free field
so that p->max_free is the size of the largest gap with one endpoint
in the subtree rooted at p. Change vm_map_findspace so that, first,
the address-based splay is restricted to tree nodes with large-enough
max_free value, to avoid searching for the right starting point in a
subtree where all the gaps are too small. Second, when the address
search leads to a tree search for the first large-enough gap, that gap
is the subject of a splay-search that brings the gap to the top of the
tree, so that an immediate insertion will take constant time.
Break up the splay code into separate components, one for searching
and breaking up the tree and another for reassembling it. Use these
components, and not splay itself, for linking and unlinking. Drop the
after-where parameter to link, as it is computed as a side-effect of
the splay search.
Submitted by: Doug Moore <dougm@rice.edu>
Reviewed by: markj
Tested by: pho
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D17794
The declaration in tcp_var.h is still around so t4_tom continued to
compile but wouldn't load. A separate commit will fix tcp_var.h
Reported By: Dustin Marquess (dmarquess at gmail)
Sponsored by: Chelsio Communications
Correct restoring was only attempted for mode 258 (800x600x4 P). (This
was the only useful graphics mode supported in the kernel until 10-15
years ago, and is still the only one explicitly documented in the man
page). The comment says that it is the geometry (subscreen size) that
is restored, but it seems to only be necessary to restore the font
size, with the geometry only needed since it is set by the same ioctl.
The font size was not restored for this mode, but was forced to 16.
For other graphics modes, the font size was clobbered to 0. This
confuses but doesn't crash the kernel (font size 0 gives null text).
This confuses and crashes vidcontrol. The only way to recover was to
use vidcontrol to set the mode to any text mode on the way back to the
original graphics mode.
vidcontrol gets this wrong in the opposite way when backing out of
changes after an error. It restores the font size correctly, but
forces the geometry to the full screen size.
r80270 has the usual wrong fix for unsafe signal handling -- just set
a flag and return to let an event loop check the flag and do safe
handling. This never works for signals like SIGBUS and SIGSEGV that
repeat and works poorly for others unless the application has an event
loop designed to support this.
For these signals, clean up unsafely as before, except for arranging that
nested signals are fatal and forcing a nested signal if the cleanup doesn't
cause one.
method as in /bin/sh.
We still do technically undefined things in the signal handler, but it
is safe in practice to access state that is protected by INTOFF/INTON.
In a recent commit, I sprinkled VGLMouseFrozen++/-- operations in
places that need INTOFF/INTON. This prevented clobbering of pixels
under the mouse, but left mouse signals deferred for too long. It is
necessary to call the signal handler when the count goes to 0. Old
versions did this in the unfreeze function, but didn't block actual
signals, so the signal handler raced itself. The sprinkled operations
reduced the races, but when then worked to block a race they left
signals deferred for too long.
Use INTOFF/INTON to fix complete loss of mouse signals while reading
the mouse status. Clobbering of the state was prevented by SIG_IGN'ing
mouse signals, but that has a high overhead and broke more than it
fixed by losing mouse signals completely. sigprocmask() works to block
signals without losing them completely, but its overhead is also too
high.
libvgl's mouse signal handling is often worse than none. Applications
can't block waiting for a mouse or keyboard or other event, but have
to busy-wait. The SIG_IGN's lost about half of all mouse events while
busy-waiting for mouse events.
allocate_tls_offset returns true on success. The same issue existed
on arm and was fixed in r345693.
PR: 236880
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
allocate_tls_offset returns true on success. This still needs more
testing and review, but this change is consistent with other archs.
PR: 236880
Reported by: Andrew Gierth <andrew@tao11.riddles.org.uk>
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Summary:
kexec-lite cannot currently handle multiple PT_LOAD segments. In some
cases the compiler generates multiple PT_LOAD segments for an unknown
reason, causing boot to fail from kexec-lite.
Submitted by: Brandon Bergren (older version)
Differential Revision: https://reviews.freebsd.org/D19574
Summary:
With a sufficiently large TOC, it's possible to index out of range, as
the immediate load instructions only permit 16-bit indices, allowing up
to 64kB range (signed) from the base pointer. Allow +/- 2GB range, with
the medium code model TOC accesses in asm.
Patch originally by Brandon Bergren. The issue appears to impact ELFv2
more than ELFv1.
Reviewed by: luporl
Differential Revision: https://reviews.freebsd.org/D19708
fuse(4) was heavily instrumented with debug printf statements that could
only be enabled with compile-time flags. They fell into three basic groups:
1. Totally redundant with dtrace FBT probes. These I deleted.
2. Print textual information, usually error messages. These I converted to
SDT probes of the form fuse:fuse:FILE:trace. They work just like the old
printf statements except they can be enabled at runtime with dtrace. They
can be filtered by FILE and/or by priority.
3. More complicated probes that print detailed information. These I
converted into ad-hoc SDT probes.
Also, de-inline fuse_internal_cache_attrs. It's big enough to be a regular
function, and this way it gets a dtrace FBT probe.
This commit is a merge of r345304, r344914, r344703, and r344664 from
projects/fuse2.
Reviewed by: cem
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D19667
From Jake:
iflib_if_transmit returns ENOBUFS when the device is down, or when the
link isn't active.
This was changed in r308792 from return (0), so that the function
correctly reports an error that it was unable to transmit.
However, using ENOBUFS can cause some network applications to produce
the following or similar errors:
"ping: sendto: No buffer space available"
This is a bit confusing as the real cause of the issue is that the
network device is down.
Replace the ENOBUFS return with ENETDOWN to indicate more clearly that
the reason for the failure to send is due to the network device is
offline.
This will cause the error message to be reported as
"ping: sendto: Network is down"
Submitted by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed by: shurd@, sbruno@, bz@
MFC after: 1 week
Sponsored by: Intel Corporation
Differential Revision: https://reviews.freebsd.org/D19652
From Jake:
The iflib_device_register function takes the CTX lock before calling
IFDI_ATTACH_PRE, and releases it upon finishing the registration.
Mirror this process in iflib_pseudo_register, so that we always hold the
CTX lock during the attach process when registering a pseudo interface
or a regular interface.
This was caught by code inspection while attempting to analyze where the
CTX lock was held.
Submitted by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed by: shurd@, erj@
MFC after: 1 week
Sponsored by: Intel Corporation
Differential Revision: https://reviews.freebsd.org/D19604
CAM IOCTL interfaces traditionally mapped user-space data buffers to KVA.
It was nice originally, but now it takes too much to handle respective
TLB shootdowns, while small kernel memory allocations up to 64KB backed
by UMA and accompanied by copyin()/copyout() can be much cheaper.
For large buffers mapping still may have sense, and unmapped I/O would
be even better, but the last unfortunately is more tricky, since unmapped
I/O API is too specific to struct bio now.
MFC after: 2 weeks
Sponsored by: iXsystems, Inc.
lagg_bcast_start appeared to have a bug in that was using the last
lagg port structure after exiting the epoch that was keeping that
structure alive. However, upon further inspection, the epoch was
already entered by the caller (lagg_transmit), so the epoch enter/exit
in lagg_bcast_start was actually unnecessary.
This commit generally removes uses of the net epoch via LAGG_RLOCK to
protect the list of ports when the list of ports was already protected
by an existing LAGG_RLOCK in a caller, or the LAGG_XLOCK.
It also adds a missing epoch enter/exit in lagg_snd_tag_alloc while
accessing the lagg port structures. An ifp is still accessed via an
unsafe reference after the epoch is exited, but that is true in the
current code and will be fixed in a future change.
Reviewed by: gallatin
MFC after: 1 month
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D19718
and use the space to make the "tps" one character longer.
It makes the iostat(8) output a bit less messed up.
Reviewed by: allanjude
MFC after: 2 weeks
Sponsored by: Klara Inc.
Differential Revision: https://reviews.freebsd.org/D19710
This makes it easier for googletest users to leverage googletest, instead of
forcing them to plug GTEST_CXXFLAGS into CXXFLAGS manually (resulting in
unnecessary duplication).
I will be following this up with a more proper fix in src.libnames.mk, as
src.libnames.mk should be automatically adding this directory to
CFLAGS/CXXFLAGS when private libraries are referenced. Not doing so can result
in mismatches between base-provided private library's and ports-provided
library's headers.
While here, tweak the comment to clarify what the intent is behind spamming
CXXFLAGS.
MFC after: 5 weeks
MFC with: r345203
Reported by: asomers
Reviewed by: asomers
Approved by: emaste (mentor)
Differential Revision: https://reviews.freebsd.org/D19731
